The present invention relates to a carpet having improved antistatic properties and to a process for the preparation thereof. More particularly, the invention relates to graft polymerization of a polymeric salt to a polyester or polyamide carpet to improve its antistatic properties.
When carpeting is conventionally manufactured, the fibers or pile are tufted on a relatively pliable primary backing which may be manufactured from any suitable materials such as jute or a man-made fiber such as polypropylene. The nonwear side of the backing is then coated with a bonding material of any suitable type such as latex. The latex serves to satisfactorily hold the fibers in place so that they cannot be pulled free from the primary backing and also to bond the primary backing to the secondary backing. In the past, clay has been added to the latex as a filler to reduce the cost of the bonding compound. The secondary backing, which may also be jute or artificial fiber, strengthens the carpet and ensures that the bonding material does not come into contact with the floor upon which the carpet is laid.
A number of proposals has been made for grafting a selected material to the surface of synthetic fibers, fabrics, carpets and other substrates to improve properties such as dyeability, antistatic properties, resistance to soiling, abrasion resistance and wettability. The most pertinent prior art is believed to be U.S. Pat. No. 3,600,122 which discloses grafting an ethylenically unsaturated monomer to a polymeric substrate that has been activated for said grafting by subjecting the substrate to a spark discharge in a zone of free radical initiating gas. Other patents relating to graft polymerization include U.S. Pat. Nos. 3,088,791; 3,092,512; 3,188,228; 3,313,591; 3,412,176; 3,670,048; 3,977,954, and British Patent Specification No. 923,851.
Although these patents constitute a major contribution to this art, investigations have been continued to develop an improved antistatic carpet wherein the antistatic properties are particularly durable to usual carpet cleaning procedures.